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' ROTA'RYBNGINE. No. 274.478. Patented Mar. 27, i883.

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ROTARY ENGINE. No. 274,478. Patented Mar. 27, 1883.

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UNTTED STATES PATENT rrr-ice.

ISAAC NEWTON FORBES, OF LLUVRENOE CO UNTY, DAKOTA TERRITORY.

ROTARY ENGlNE.

SPECIFICATION forming part. of Letters Patent No. 274,478, dated March 27, 1883.

Application filed July` 26, 1882.

[lo all whom t may concern:

Beit known that I, lsnsc NEWTON Fosses, of Lawrence county, Territory ot' Dakota, temporarily residing at Y'Vnshingtou, in the District of Columbia., have invented a new and useful Improved Troonilic or Rotary Engine,

of which the following is a specification.

The subject ofV my invention is a trochilic or rotary engine with two piston-wheels, with two teeth to each wheel attached to one shaft, and two abutment-rollers to each pistonwheel, which may be of one-halflhe circumference of the piston-wheel, and are geared so as to rotatein unison therewith, and are formed with cavities to pass the piston-teeth and with counterbalance-chamhers at the opposi te sides; also, with alpair et' automatic fourfold cnt-oit' valves at diametrically-opposite points in the cylinder-casingforeach respective piston -wheel adjacent to the abutment-rollers, serving to ont citi` the steam at any desired proportion of the revolution consistent with the design or make ofthe engine, causing it t work steam or other motor power expansively. The relative positions ot' the piston-teeth on their respective piston-wheels stand quartering, or aten angle ot' ninety degrees to each other. The piston-teeth-are formed with tongues or Shanks ttting in longitudinal grooves in these wheels and secured by bolts. They are also provided with packing-pieces pressed outward automatically by springs or steam, or both, in contact with the inner surfaces of the cylinders. The working-surfaces ot the cylinders and of vthe piston-wheels arei'or the most part made np of removable segments'composed ot'ubbitt or other suitable metal cast into suitable seats, or of other hard metal slipped in, as hereinafter described. The steam is taken in in a direction radial to the cylinders around which it is conducted, so as to enter at two diametricallyopposite points, in order to balance the pressure, while the exhaust-passages are arranged l on the outside ofthe live-steam channels in the respective cylinder-cases, in order to pre- 'ventthe live steam from loss of heat by radiation, and at the same time make firmer and more rigid .steam cylinders or casings therereference to the accoiugauying drawings, in which- Figure l is a transverse section through the casingand cylinder, illustrating the shaft, pistou-wheel, abutment-rollers, and valves. Fig. 2 is a horizontal plan view ofthe engine, partly in sectiom Fig. 3 is a vertical longitudinal section ot' the engine, the base being broken. Figs. et and 5 areoutside views otontside heads, showing tappets and cnt-cti' valve-gear. Fig. 6 is the central head, partly in section, with induction-steam fitting partly broken oft', the section-line ot' the center bearing being on line with the surface of the head and the remainder of the section being central. Figs. 6a and and Gl are sectional views of a central head on the line 6, Fig. 6.- Fig. 7 is a longitudinal central sectional view of the main-shaft hearing in one ot the outside heads partly broken. Fig. 8 is' a top view with cap 263 full, partly removed, showing pinion and gear fnll,.with

shaft-bearings and ring in section on the line 8 8, Fig. 7, this cap 263 being shown in section in Fig. 7. Gap 263a vforms the inner bearing ot the pinion-shaft 266L and a protec# tion for the tooth-gear upon the adjustable ring 263, from interruption of the capillary material used in the oil-chamber of the head. Figs. 9 and l() are hearing-pieces, shown in full and section. Fig. 1l is a transverse section of the bearing-segments detached on the line 8 S, Fig. 7. Fig. 12 shows a sectional View ot' pinion 265 and shaft 266 complete, shown in Fig. 7. Fig 13 is a detailed longitudinal sectional view, illustrating the mode of connecting the valve-levers to the valve-stein. Figs. let and 15 are transverse sections, illustrating different modes of setting out the packing strips ofthe piston-teeth, either by steam or spring adjustment, or hothit required. When steam is used the side surface ot' the packing strips and surface in the tooth, where convenient, are Water-creased. Fig. 16 is an end view ot' one ot' the teeth detached, showing the end packing -piece removed. Fig. 17 is a longitudinal section of au end ot' the tooth, showing the end packing in elevation and end ot' packing-strip in section. Fig. 1S is aiaee View of one of the teeth. Fig. 19 is a side view of the same. Fig. 19 is a side viewot' the packing-strip detached. Fig. 20 is a cross-section through the casing,

" fz 2t-Larsl cylinder, Sac., illustrating a modification of Fig..1, showing a twofold valve and parts to suit, instead of fourfold, as in the other case. Figs. 201), 200,201, and 2()e are detailed views in section and full of a modified twofold double-faced valve. Fig. 21 is adetached sectional view of the outside head, with bearing-case and bearing, illustrated in Fig. 21, removed. Fig. 21 is a longitudinal section of the bearing-case and bearing complete removedfrom the head. Fig.21b is a sectional view of four bearing-pieces'in position on the line 2lb, Fig. 21". Figu-21C is a top view of the adjustable bearing-case 21:". y

To the main shaft 131 are secured two piston wheels, 132 and 132, connected by gearings 133 and 134 with abutment-rollers'135, so that the said rollers will rotate in unison with the piston-wheels 132 and 132I without any slip between their peripheries. Straight gearing 133'and 134 is provided at one end l and helical gear 16Sand169 at the other end of the engine. (Shown in Fig. 2.) Each pistonwheel carries two piston-teeth, 136, at diametrically-opposite points, the said teeth be-V ing formed with tongues or shanks 137, portions of which are dovetailed in grooves or recesses in the wheels, and secured by bolts 13b'. Said teeth are also provided with shoulders, serving to hold the surface-pieces 141, hereinafter mentioned. In the faces of the teeth are packing-pieces 139, pressed outward by springs or steam, or both, and where steam is used the sides of the packing-strips and inner surfaces of the teeth should be water-creased or grooved, where con venieut, to prevent leakage, the said pieces being pressed in contact ton-teeth 136 iu their revolutions.

with the inner surfaces ofthe cylinders 140.`

The working-surfaces of the piston-wheels 132 and of the cylinders 140 are made with removable segments 141 and 142. The pistou- 'wheels and segments iitting them are fitted in T-shaped grooves and tongues, as herein illusE trated, or in any suitable manner, so as to permit the said' surfaces to be readily and economically removed and reuewedyif desired. These removable surface-pieces may be made of `Babbitt or other metal poured around in a templet of the exact shape, or the surfacetached to the faces of the cylinder-heads arel illustrated at 1421L in Fig. 3.

The abutment-rollers 135 are formed with cavities 143 to permit the passage of the pis- The abutment-rollers being one-half ot' the circumference of the piston-wheel and the latter carrying two teeth, it will be evident that the single cavity 143 in each abutment-roller will be presented to receive leachof the two teeth of the piston-wheel in succession, while the piston-wheel and the abutment-rollers` are, as stated, geared s o as to rotate in unison witli out any slip between their peripheries, the

abutment-rollers necessarily performing two revolutions for every revolution of the pistonwheel. ASimilar removable segments or surface-pieces areprovided in the abutment-roller ea-sings, as shown at 144, Fig. 1, which surfacepieces maybe composed lof Babbitt or other metal poured in around va templet, which should be held in an exact central position and of the exact size required; but .it'may be dressed lout andft-ted in, corresponding with the shape ofthe recess; or they should be made the bestshape to receive the surfacepieces. The casing in which the abutmentrollers work should be water-creased, similar to the surfaces of the abutment-rollers; also, the main cylinder inwhich the piston-wheel works should have water-creases similarto those in the piston-wheel to prevent the passage of steam between the 'surface of the teeth and that of the cylinder, thus insuring safer joints, the surfaces of thepacking-pieces in the teeth being likewise'water-creased.

145 represents holes or chambers in the abutment-rollers for counterbalancin'g` the re-l cesses for the'piston-teeth to pass and to lig'h ten' 148, and from thenceinto therespective partsl ot' the cylinders. The live steam is conducted partly around the cylinder, where it is delivered through the valve-seats and the recesses inthe valves into the cylinder at diametrically-opposite points, in close proximity to the abutmentrollers 135, by means of fourfold oscillating cut-oit' valves 150, sothat the steam may be worked expansively during the latter part (more or less) of the movement of the teeth between the abutment-rollers. These valves have holes crossing each other, leading to opposite quarters, between the adjustable valve-pieces, which convey-live lsteam to the opposite quarters thereof, thus holdiugt-the valve in equilibrium, pressing the valves to their seats by the pressure of steam beneath the ilanges thereof. They are pressed out by means of springs, also, and, if desired, steam may be employed in connection therewith beneath the shanks in the valve-frame,` and water-cuts placed in the valve, as more fully described in another application of even date herewith, marked 0.

The exhaust-ports are shown at 152, and are constantly open, the escape of vlive steam to IOO IIO

said exhaust-ports being prevented vby the closing of the cut-off valves and their remaining closed until the piston-teeth 136 have 274,478 g fi.

passed the abutment-rollers 135 and cover the` .149, after entering the casing proper, so as to protect the latter from cooling and consequent loss of pressure ot' steam. A casing lled with a non-conductor ot' heat may also inclose the casing wholly or partially, as may be desired.

The automatic gear for operating the cut-ott' valves is shown in Figs. I and 5, that-in Fig. 4 consisting o't' valve-levers 15st, secured by pins, the to the end ot' the valve-stems, and each constructed with two arms, 155 and 156, formed with curved fingers 157, adapted to receive the impact of tappets 158 and 15), which are conrected respectively with the under side of the main gear-wheel on the main shaft and the under side ot' the pinion gear-wheels on the nbntineutroller shaft in such manner-that the contact. ofthe main gear-iv heel tappet 15S with the arm 155 will close the cut-ott' valve when the tooth has performed the desired part of its increment between the abutment-rollers, and when the teeth cover the inlet ports 151 the abutment-roller tappets, having come in contact with the arms 156, reopen the valves 150. Dotted lines for the respective teeth indicate their position when steam is first let in. The second dotted lines indicate the position when the valve is suticiently open to let the steam in between the teeth and the abutment-rollers.

ln Fig. 4 full lines indicate the position of the valve-gear when the valves are open for tnll head of steam, while dotted-lilies of the valve-levers indicate their position when the vulves are closed for rising steam expansively. u. a. and dottedlines indicate the position of the piston-teeth in the cylinder at the time the tnll head ot' steam is let on, and shows their relative position to the valve-gear.

The reverse method of cutting oti' and letting on steam ofthat shown in Fig. et is shown in Fig. 5. ln Fig. e the cnt-oit' tappets were secured to the main gear-wheel and the let-on tappet-to the respectiveabutment-roller wheels, which, when cut ofi', close the ports filled with live steam from the valveseat and leave the port from the piston-wheel open in the valve, while in Fig. 5 the let-on tappet is on the main gear-wheel and the cnt-oli` tappets are on the respective abutment-roller gear-wheels, which is readily seen from the dotted lilies ofthe relative position ot' the valve andrsteanr ports through into the cylinder. .This leaves the main livclsteam port open into the valveseat continually and-cuts oft' the live steam from the piston-wheel intothe valve-seat, thus lea ving the pressure of live steam, which has a greater head for a continual pressure ont upon the flanges of the adjustable valve-pieces to assist the springs, or the steam, it' used, within to hold the adjustable valve-pieces upon their faces, especially the one covering the inner port, which has the counter-pressure upon its face to open it, which is continually diminishing, whereasn Fig. 4 the steady live pressure from the boiler while the valve is closed, covering the inlet-port into the valve, has the tendency to onen the valve, while the pressure from within the cylinder against the tlangesof the valve-pieces, Src., is variable. Ihe difference is here shown, so that choice may be taken. I consider that shown in 5 as preferable, though both are good.

In Figs. I and 5 there are two classes of valve-levers, though their shapes for contact with the tappets are the same. 154 receives the engine-bolts in the curved slots 154c in the end, limiting the Amotion of the latter to the proper distance for let-ting on and cutting olf steam. These bolts have removable sleeves, to protect them from injury-hy the action of the valve-lever. The valve-lever 15e:L has but one bolt, extending from the head up between the arms, to perform the same function of limiting the play of the valve in cutting olf and letting on steam. This bolt has also a protecting-sleeve, to be removed at will, and the stop, permitting the play of the lever on the bolt, equals the play ot' the valve. The latter lever is, perhaps, the most simple, though either may be used.

lt will here be noticed that the valve-tappets, respectively in Figs. 4 and 5, have much more of their continued circumferential sur` face than those used in cut-off reversing-engines described in other applications of even date herewith. The object ot' this is to hold the end of the valve-levers in their respective positions-either open or closed, as the case m a y be--until their opposite tappets are ready to take the opposite arm. When the tappet leaves the arm the others take the opposite end to reverse the valve. Full lines indicate the position for cutting off and letting on, while dotted lines indicate the relative position of the piston-teeth and recesses in the abutment-rollers.

In Fig. 5 the circoli tappets upon the abutment-roller gearing have provisions made for setting forward or back, one having a slot',the other having holes in it. Either one of these devices may be adapted for the purpose of increasing or decreasing, as the case maybe, the relative proportion of the revolution before cutting off for using steam expansivelv, which tappets are secured tirnly to the gearwheels, respectively. A double engine of this character, while working steam or other motorilnid expansively and in the most economical manner, is rendered smooth and uniform in its action by the induction and eduction of steam upon the respective piston-teeth and in harmony with the momentum of the pulley, and by the complete opening of one pair of valves before the others, as above shown, the pistonteeth being arranged in alternate positions for this purposefas before explained.

lOO

IOS

The construction of the casing and the arrangement of the steam passages and ports through the saine are very simple. rlhe outer and inner casing are united with partitions or bridges and ties, as may be desired, which will form rigid cylinders and casings for the working parts of the engine. The inlet and exit channels for the induction and exhaust steam are indicated by arrows in the respective figures, l and 20, the latter being a modiiication ofthe former, and forming an extremely simple casing and cylinder with their adjuncts. The respective walls of the induction and exhaust ports are united firmly` by bridges, connecting the same together at short distances apart, leaving sufiicient area for receive and exhaust ports.

The gearing which connects the pistonwheels with the alnitment-rolleis, so as to compel thein to rotate in unison, is represented in plan view, at 133 and 134, iii-Fig. 2 in the form of simple cog-wheels and pinions at one end and helical gear 16S 169 at the other, and thus guarding against the possibility of lost motion by end adjustment of the helical gear or gearing to suit; or the helical gear may be used at both ends ofthe abutment-rollers and the main shaft, as shown in Fig. 3; or the gears may be cut in two transversely and adjusted to prevent lost motion ot' rotary engines, which will be the subject of' other applij cations soon.

A horizontal longitudinal central section of the center head is illustrated on the line 6L of Fig. 6, with the convex movable part of the head which supports one end ot' the main bearing-case and bearing removed, which lat-4 Ter is illustrated in detail in Fig. 6*. rlhis part is made separate, and screwsinto the main part ot' the center head and t'orms a part thereof. It also screws upon the end bearing-case, and forms a support thereto, thus completing the head, which, when secured to its position, answers the saine purpose as when cast solid in one piece. The objectv of castingthis piece separatel is for the purpose of inserting the center bearing, without which it would be impossible to do so, as herein shown.

The adjustable bearings 3l and removable pieces 32 are removed irom their positions in the center head, permitting the center journals ofthe abutment-rollers to slip in their respective bearings when the adjustable bearings 3l and removable pieces 32 are replaced in't'heir position. The pieces may be provided with tongues, with corresponding grooves in their seats in the slots or recesses in the head, in which they iit for the purpose of securing them laterally to the head in their positions;

or they may each be. provided with groovesA and separate tongues slipped in for the purpose ot' performing the same office. These removable pieces are secured to the head by bolts 33 intheir positions, andheld rmly thereto, the bolts being secured from turning by lock-washers.

The automatic followers 34 have colla`rs42,

which receive the pressure ofthe springs 36, and lauxiliary springs 4.214 are placed at the end forholdiug the adjustable bearing-piece, abutment-roller,andjournal in their respective positions, as shown in Figs. 6 and 6a.

The catch 43a holds the cap-nut 37 from turning, and is heldin position by a rin 0. The spring-catch t3a is thrown out ot' connection with the cap -nut by the application ot a wrench or key which turns the said cap-nut. This head is fully explained in other applications of even date herewith.

In the several heads of the engine are located all the bearings proper. The main-shaft bearing in the center head, as illustrated, has four adjustable bearing-pieces, 251, placed at opposite quarters, with two projections on the back ofeach bearing-piece, which pass through mortises in the bearing-case, and have eccentric backs, over which a ring, 252,-is tted that encircles them, with recesses therein containing eccentric segments corresponding with the eccentric Vbacks of the vbearing-segments. This ring hasa worm tooth-gear upon part ofits periphery, with an endless screw iitting therein on a shaft", 255, extending to theoutside of the head, (shown and described fully in other applications ot even date herewith,) which, when turned by key or wrench, adjusts the bearing centrally with the cylinder upon its shaft, thus securing a continual central posi ltion of the piston-wheels to their cylinders, which, as before remarked, is indispensable to the success of the engine.

I do not confine myselt to two eccentric backs and two inortises inthe vbearing-case for each adjustablepiece; nordoIconiine myselfto four bearing-pieces for the main-shaft bearing ofthe centerhead; nor to one ring, worm-gearing, shaft, tbc., for holding and adjusting the bearing-pieces, as the size and length ot' the bearings have much to do with the construction, the number ot' bearing-pieces, and linmber' and size ot' the mortises through the casing, and the projections passing through the same and ltheir locations.

The'main-shat't bearings in the outer heads are composed ot' adjustable bearing-pieces 261, iitted in their respective casings 264. (See Figs 7, S, 9, l0, 11,218, and 2lb.) Thebearing-case is cast separate from the outer head (seeFig. 21u) for the purpose ot' inserting the bearing, which,when screwed in the head and secured from turning by bolt 147a or otherwise, forms a part ofthe head, as though cast in one piece. This casing is tirst bored out the proper shape and the ends dressed to receive the ends ofthe adjustable bearing, as shown inFg. 2l, withthe ends of the bearing-segments dressed to'tit, which form partial radial guides to the adjustable pieces, they then being placed in position and a shaft or templet ot' the proper size placed in the bearing.- Af- IDO IIO

ter thepieces are all in position Babbitt or other i bearin gs.

bearing-piecesto hold theBabbitt. Holes may wear produced by the weight of the pistonbe bored in the casing, if required, or either one used to secure the Babbitt in position; or other metallic pieces, dressed to suit, may take the place of the Babbitt,and secured by screws to the casing, forming complete guides to the bearing-pieces. The casing is provided with mortises through-it for the purpose of allowing the inclined backs 262 and 262. of the bearing-segment to pass through, which tit the inclines of an encircling ring, (see Figs. 7 and 8,) which ring incloses the bearingcase and bearing,.witl1 corresponding inclines upon its inner' surface, corresponding with the inclined backs of the bearing-segments. It also has upon its inner surface a screw-thread, tilling a corresponding screw upon the outer surface ot the bearing-case 264. These screw-th reads enable the ring 263 to move longitudinally when turned thereon by means of a toothed gear upon the outside of the ring 263. (Sec Figs. 3, 7, and 8.) These teeth t the pinion 265, secured to the bolt or shaft 266e, with its appendages, (see Figs. 7, 8, and 12,) which, when `the wrench is applied through the outer cover in the main gear-wheel, imparts the necessary rotary motion to the encircling ring 263, and thus screwsit upon the bearing-casing in order to move the encircling ring longitudinally,'and` so press the inclined backs ot' the bearing-seg,

ments in upon the shaft, and thus secure a central adjustment of the bearing upon .the main shaft. By this means a continued central position of the piston-wheels to their cylinders is maintained, which is indispensabletorthe success of the trochilic or rotary engine. This position is scoured to each of the main-shaft In the end heads, as in the center-head mainshaft bearings, I do not confine myself to the number of bearing-segments employed in each bearing, or the number of inclined backs thereon, or the number of mortises in the casing for the backs to pass through, or the number of pin'ions employed to turn the encirciing ring, ortho number of rings employed to lill that oftice of adjusting the bearing-segments centrali bearings removed from the casein a sectional view on the line 2l.b of Fig. 21u. Fig. 21c is an end view of the bearing-case 264.

The sectional 4viewsin Figs. S and 11 show methods of manufacturing the different bearing-segments, three of these segments being babbitted andoneshown solid. Eitherthe solid or babbitted bearing-pieces should be adopted, but not conjointly, but a harder bearing-piece may be used in the bottom to sustain the extra wheel, Src., thus assisting the maintenance of the central position. The inclined projections in two of the bearings are smaller, showing the diiierent methods of construction only.

In Fig. 11 the four bearing-pieces are illustrated in detail view, partly in section and partly in full in their relative position as they would be in the casing.

1n Fig. the adjusting-bolt 266 and pinion 265 are shown in gear, with the adjustable toothed ring 263, with all the appendage in the casing complete, and details of the pinion 265 and of the shaft., with all its appendages, and a broken piece of the bearing-casing are shown in Fig. 12. 266 is the bolt proper. 267 is the adjustable pin which tits in the bolt. 269 is the coil-spring in the bolt around thepin. 268 is the rivet which passes through the ratchetring 270 from side to side, and through a slot in the bolt and tightly through the adjustable pin 269, the ends being riveted suiiciently to hold all in position when the bolt is placed in position in the casing. The annular ratchet cap ring 271 is placed over the boltin the recess of the casing, and bolted or riveted firmly thereto, the pinion beingplaced upon theinner end of the shaft or bolt and 4secured thereto by rivets or screws or otherwise, and in gear with the adjustable toothed ring.

itis evident that when the wrench is applied to the end of the bolt or shaft rmly with the inner portion pressing against the outer end of the adjustable pin 267 that it will play in the seat in the bolt and carry the ratchet-ring 270 in the recess in the casing made to suit, and thus throw the two ratchet-faces out of gear and allow the bolt to tnrn freely, which carries the pinion, and thus turns the adjustable toothed ring 263 upon the screw and ad# justs the bearing,`as heretofore stated, to take up the wear upon the main-shaft bearing, and when the wrench is withdrawn the ratchets at once are thrown in gear by the spring pressing outwardly upon the shoulder of the pin. The wrench has to pass through holes in the outer or end covers and in them ai u gear-wh eels to get to the adjustable bolt 266, for adjusting the bearings by the inclines upon their backs coming in contact with the inclines in the adjustable rings, thus securing a contin nous central position of the piston-wheelsito their cylinders. Two or more of these pinion-wheels and appendages complete, as described or otherwise, instead ot' one in contact with the toothed gear ofthe adjustable ring 263, placed at convenient parts of the c'asin g, may be used, if necessary.

270 and 271 are ratchet-rings shown in full and in section separated and together, respectively. j

'lhe piston'wheel teeth, as illustrated in details in Figs. 14 and 15, are provided in their faces with packingstrips 13S).

Various modes of adjustment of pushingpieces may be employed, such as `by means of springs or steunrducts, as illustrated, or both.

These packing-strips 139 are grooved at their l lowed to compensate for contract-ion and exedges to receive side tongues in the toothgroove, in which they tit,which occupy the side grooves, so as to conne the packing-strips within their seats inthe teeth, hutallowing sufficient play to permit the packing-strips in the teeth to be forced radially'outward in contact with the surface 142 of the cylinders, and thus secure steani-tightjoints upon their surfaces, and may be assisted by water-cuts in the cylinders or their surface-pieces.'

The ends of` the teeth are provided with packing-pieces 275, wl1iclif liave a little endplay beneath their surfaces, thus providing` for the difference ot' expansion and contraction of metals and preventing end binding of the tooth. These pieces iit in the recesses in the ends of the teeth, and are pressed outward by springs 276 or steam; or both may be employed, if desired, to press the packing-pieces in contact with the surface-bearing pieces 142m, and form steam-tight joints therewith. 1n case steam is employed, the construction of the stem ot' the packing-piece of the hole corresponding should -be made in harmony therewith, with water-creases around it.

In the respective heads are packing-rings 277, pressed out by springs 27S in contact with the rim of thegwheehwhich produce `steamtightjoints. These springs have play beneath their surfaces to com pensate for expansion and contraction of metals, and thus prevent end binding.

The abutment-rollers l35`are also provided with packing-rings 279 to perform the same office in producing tight joints with play beneath the rings to prevent end binding. These rings press against the plate covering theend-ot the recess in the' abutment-rollers, and produce the tightjoint more fully described in other applications of even date herewith.

Fig. 16 illustrates an end view of the tooth with the end packing-piece, 275, removed.

A sufficient number of water-cuts are provided in the respective packing-rings and the surfaces in which they work to prevent leakixg constructed in harmony therewith.

age of steam.

In Fig. 2() a modified form of this engine isl illustrated. Its main feature is a twofold valve instead of the fourfold valve, heretofore described, with induction-ports and engine-caslndnetion-ports and steam-channels are placed to correspond with the two-faced valve in the respective seats. 'lhe construction of this valve and the engine casing or cylinder is sim-l pler than those previously described, and makes a most complete cut-ott' non-reversible engine. In Figs. 20, 20h, 200, 20d, and 20e these twofold and two-faced valves are more fully illustrated in sectional and full views. Fig. 202u is a longitudinal sectional view of' one ofthe valves complete with the stems broken, showing the method of springs to hold the valves proper upon their seats, also the steamducts conveying steam between the valveshanks and frame, in which a little play is alpansion, thus preventing the valve from sticking. The frame is grooved between the valvestems from endto end of the valve for the valveshanks to lit in. The ends may have `stops inserted equal to the thickness of the collars I' and the ends of the valveshanks notched to suit, the object of which is to produce steamtight joints, in combination with the valve packing-rings in the heads. A notch is also turned inside of the collar of the valve-frame, n

in which the respective flanges fit endwise, steam always working beneath the flanges and the frame to hold them against their respective faces.

150b represents the valve-frame proper with the stems, and 150' the adj ustable Valve-pieces.

Two modes of pressing outward the adjustable valve-pieces proper on the face of the valveseats are shown, such as springs and steamducts.

lt will be'seen that by means of holes in the main frame-work of the valves live steam is supplied to both si'desof the valves, thereby producing an equilibrium, while in the fourfaced valve, as illustrated in Fig. 1, live steam is conducted to the four opposite surfaces with holes crossing each other, and thus producing an equilibrium therein. InY this respect the A fourfold valve differs from any heretofore m entioned inany of the previous cases. This fourfold valve is applicable to a non-reversible engine only when the live steam from the boiler direct occupies the opposite four quarters. So, also, is the twofold valve applicable only to a non-reversible engine when counterbalanced by live steam from the boiler direct on each side ot' the valve.

The twofold valve 150% Fig. 20, will be made the subject of a separate application. i

Having thus described my invention, what l. claim as new, and desire to secure by Letters Patent, isl i 1. The double non-reversible tro'chilic or rotary engine constructed with two piston-wh eels on one shaft, each having two teeth, with the teeth on one wheel opposite the spaces between the teeth ot' the other wheel, two cutoff valves at opposite points in each cylinder, two valveless discharge-ports at two other opposite points, and automatic cut-off gear, all

substantially as herein shown and described.

2. A center head with four valve-stem bearingstwo ou each side-and valve packingrings, and with adjustable abutment-roller bearing, and their automatic or screw followers, in combination with two toothed pistonwheels and abutment-rollers, for .the purpose set forth.

3. Theend heads having two valve-stein IIC bearings in each head, with valve packingrings, springs, Snc., for forming steam-tight joints endwise and prevent end. binding, and the adjustable abutment-roller journal-bearings, with their automatic or stationary followers, in combination with abutment-rollers, two toothed piston-wheels, and condense-water channels and cylindercocks, substantially as and for the purposes set forth.

4. A trochilic or rotary engine piston-wheel, 132, provided with surface-pieces 141, pistonteeth 136, holding said surface-pieces, packing-strips 139, and springs 274, in combination with the packing-strips 139 and packing-pieces 275, and spring 276, substantially as and for the purposes set forth.

5. A rotary piston -tooth, 136, in combination with paclringstrip 139, spring 274, and

end packing-piece, 275, spring` 27 6, and watercreases therein, substantially as and for the purposes set forth.

6. In a trochilic or rotary engine, the combination of one or more toothed piston-wheels, two or more recessed abutment-rollers for each of said pistou wheels, straighttoothed gearwhecls 183 181, connecting the shafts of the pistouwheel and abutment-rollers at one end thereof and helical gear wheels connecting said shafts at the other end thereof', to prevent lost motiou,to preserve steamtight joints, and permit the tightening of all the gear-wheelsby longitudinal adjustment of the helical gears, substantially as set forth.

7. The adjustable bearing-segments 261 for the main-shaft hearing, and housing or casing 264, in which they lit, and a ring, 263, havin-g inclines corresponding with the iuclines of the backs of the bearing segments to lit and adjust the same, with screw -thread therein fitting the screw-thread of the bearing casing or housing, and a tooth gear upon the o'uter surface of the ring` with pinion 265, hollow shaft 266, pin 267, spring 269, gear or ring 271, having serrated face with corresponding serrated ring, 270, and rivet 26S, Sto., substantially as and for the purpose set forth.

S. The combination of the end head, the shaft-bearing therein, and the removable cas ing covering said bearing, substantially as and for the purposes setforth.

9. The .fourfold cut-oft' balanced valves,with connected ducts crossing each other through the valves, permitting steam to pass freely to the four opposite recesses in the valves, and thus counterbalance the pressure thereon, substantially as and for the purposes set fort-h.

10. A removable convex and concaved end of a center head for the purpose of inserting the main-shaft bearings, substantially as and for the purposes set forth.

11. The adjustable segme'nt-hearings, with one or more inclined backs thereon, and housing or casing having mortises corresponding with the projections of the seg1nentbacks, and an encircling ring or rings fitted as described, tooth-gear thereon, and a pinion with its ailjuncts to hold all in position, substantially as and for the purposes set forth.

12. The combination of the toothed pistonwheel, recessed abutment rollers, t-appets, valve-levers, and stops, constructed and operating as and for the purposes herein set forth.

13. The combination of the center projections, 142, in the end heads with the central projections, 142, in the center heads and cylinders, pistonwheels, and main-shaft bearings in each of the cylinderheads, substantially as'specilied.

14. A valve-seat bushing, in combination with the fourfold balanccvalve, having inlet and exit live-steam ports through the sanne without any exhaust-ports therein, substantially as and for the purposes set forth.

15. In'a rotary engine, a removable piece, 32,'having flanges and boss, with bolts 33, for

securing it in place,and provided with tongues Y and grooves, followers 31, springs 36 and 42,

spring-catch 43, and hollow cap-nut 37, substantially as and for the purpose specified.

16. In a rotary engine, the combination of automatically adjustable bearing segments with the abutment-rollerjournals in the heads, substantially as set forth.

17. In a rotary engine, a central main shaft provided with a tapered portion for securing a piston-wheel, having stops therein and cor'- responding recesses in the wheel, a thread and nut with internallythreaded pins, substan tially as and for the purpose specided.

I. N. FORBES.

In presence of- ERNEST ausencias', FRED. Lf'FosrnR. 

